Beauty care compositions, particularly hair coloring and/or bleaching compositions and/or heat-generating cosmetic compositions, may involve reactive chemistry, as they comprise ingredients undergoing a chemical reaction when placed in contact with each other. For example, oxidative hair color compositions comprise a primary precursor (also called coupler), a secondary precursor (also called developer) and an oxidizing agent such as ammonia. When mixed together, a chemical reaction occurs so that a dye is formed.
Such chemical reaction is wanted upon application onto hair, but not before. For avoiding the chemical reaction to occur prematurely such as upon manufacture and/or upon storage, these ingredients are usually comprised within different components, such as a first component (also called a tint) comprising the primary precursor and a second component (also called the developer) comprising the secondary precursor. These components may be sold as a kit and be packaged individually in any suitable packaging, wherein these kits comprise at least two components to be mixed extemporaneously i.e. shortly before application onto hair.
Professional hairdressers are usually mixing the different components using a bowl and a spatula. Untrained users such as consumers coloring their hair by themselves are not willing to mix the components in a bowl, as the mixture obtained may lack homogeneity, leading afterwards to an uneven hair coloration and also because such process is uneasy to achieve, and may lead to staining the area where the mixing is taking place e.g. the sink, the bathtub, and/or the floor.
For avoiding such drawbacks, hair coloring and/or bleaching kits are usually provided with at least one squeezable plastic container comprising about 70% or less of a component upon storage. At least one of the other components is poured into the container, mixed together with its content, and the resulting hair coloring and/or bleaching composition is applied onto hair by squeezing the plastic container.
Such type of containers while being convenient upon use, have shown drawbacks upon storage. Indeed, they usually comprise relatively thin panels in order to be squeezable i.e. deformable upon application of localized pressure onto the container by hand without excessive force. However, as these containers are filled with about 70% or less of a component, there is a substantial residual volume filled with gas e.g. ambient air at the place of manufacture. Upon certain circumstances such as a change of temperature and/or a change of altitude, there may have a significant pressure differential between the environment and inside the container. Such differential often leads to an uncontrolled, random deformation of the container. This is unwanted as the container may not be appealing to the consumer, may look defect and/or may even induce the leaking of its content and/or its breakage.
Different solutions have been provided for avoiding these drawbacks. For example, containers comprising thicker labels and/or labels made of more rigid plastics have been provided. These containers require however an increased force for being squeezed, which is inconvenient upon use by the consumer. Containers having pressure-regulating means have also been provided. Such means are usually sophisticated and therefore expensive to be manufactured. It also usually requires at least one additional process step for affixing them onto the container and/or the sealing means. This drives the cost of manufacture up, and impacts negatively on the price of sale of the hair coloring and/or bleaching products and/or kits.
There is a desirable need therefore of providing a hair coloring and/or bleaching product comprising a squeezable plastic container containing upon storage about 70% or less of a hair coloring and/or bleaching component, which is resistant to random, uncontrolled deformation under a substantial pressure differential between the environment and inside the container. There is also the desirable need for providing a hair coloring and/or bleaching product comprising a squeezable plastic container being resistant to uncontrolled deformation, which has an affordable cost of manufacture. There is also the desirable need for providing a hair coloring and/or bleaching product comprising a squeezable plastic container being resistant to uncontrolled deformation, which is appealing to the consumer yet easy to use.